DeVito played "Martini" in the movie One Flew Over the Cuckoo's Nest (reprising his role from the 1971 off-Broadway play). After Taxi, DeVito continued what became a successful movie career, beginning with a role in 1983's Terms of Endearment (in an almost walk-on role) and the comic rogue in the romantic adventure Romancing the Stone, starring Michael Douglas and Kathleen Turner. All three reprised their roles in the 1985 sequel, The Jewel of the Nile. In 1986, he was in Ruthless People with Bette Midler and Judge Reinhold. In 1987, DeVito made his feature directing debut on dark comedy Throw Momma from the Train, in which he additionally starred, opposite Billy Crystal and Anne Ramsey. Two years later DeVito reunited with Douglas and Turner to direct and star with them in The War of the Roses.

Other notable work during this time includes Other People's Money with legend Gregory Peck, director Barry Levinson's Tin Men as a competitive salesman to Richard Dreyfuss, two co-star